Method of producing detergents



Patented July 7, 1942 METHOD OF PRODUCING DETERGENTS TorstenHasselstrom, Savannah, Ga., assignor to G & A Laboratories, Inc.,Savannah, Ga., a corporation of Georgia No Drawing. Application February8, 1940, Serial No. 317,993

2 Claims.

This invention relates to an improved method of producing a detergentand wetting agent from pseudopimaric acid.

In my U. S. Patent 2,121,032, issued June 21, 1938, the method ofpreparation of a detergent and wetting agent by treatment ofpseudopimaric acid with a sulfonating agent and the product so obtainedare described and claimed. The product is described as a sulfonic acid.

Now, in accordance with this invention, an improved method of producinga sulfonic acid derivative from pseudopimaric acid is described. My newmethod provides many advantages in is treated with a suitable calciumsalt such as, for example, calcium carbonate, calcium bicarbonate,calcium chloride, etc. so as to form the calcium salt of the sulfonicacid of pseudopimaric acid contained in the brownish product. Thecalcium salt of the sulfonic acid may then be purified by any convenientmeans such as by the preparation of the sulfonic acid over the methodsbroadly described and claimed in my above-identified patent. By myimproved method of preparation the sulfonic acid derivative may beisolated in a higher state of purity and by a more simplified process.My improved process also is more readil adapted to commercialproduction.

In my above identified patent I refer for a description of pseudopimaricacid to an application for United States Letters Patent, Serial No.675,976, filed June 15, 1933 and now issued as Patent No. 2,072,628. Ialso in my Patent No.

2,121,032 describe the pseudopimaric acid at considerable length.Further identification of pseudopimaric acid for the purposes of thisinvention is unnecessary.

The first step of my present invention comprises sulfonation bytreatment with concentrated sulfuric acid of pseudopimaric acid or ofmixtures containing pseudopimaric acid, such, for' example, as resultfrom suitable heat-treatment of wood and/or gum rosin. The sulfonationmay be carried out, if desired, in a suitable solvent attacked orunattacked by concentrated sulfuric acid, e. g., carbon tetrachloride,liquid sulfur dioxide, petroleum distillates, saturated and/orunsaturated hydrocarbons, preferably of the aromatic and/orhydroaromatic series, although I may employ unsaturated aliphatichydrocarbons, or mixtures thereof.

As sulfonating agent I preferably employ sulfuric acid of specificgravity about 1.84, although I may employ somewhat lower or somewhathigher strengths, even to fuming sulfuric acid, or chlorsulfonic acid orsulfur trioxide as the sulfonating agent.

The sulfonation "mixture obtained is then treated with water at atemperature below about 100 C. As a result of this treatment, a brownishprecipitate is separated. After washing to free residual sulfuric acid,the brownish precipitate extracting with an organic solvent, as forexample, ethyl acetate, benzol, carbon tetrachloride, tetrachlorethane,etc. The salt may then be acidified so as to free the sulfonic acid ofpseudopimaric acid in purified form.

The quality of the sulfonic acid obtained by following my improvedprocedure involving formation of the calcium salt of the sulfonic acidas a means of separation from the residual sulfonation materials issuperior to that obtained by employing the hot water extractionprocedure described n my prior patent.

As an example of the procedure for carrying out my invention, thefollowing may be cited:

Ezrzmpie I was then poured onto 200' parts by weight of cracked ice. Thetemperature was not allowed to go above 20 C. Then 200 parts by weightof water were added. A brownish precipitate separated and was filteredoff, washed with water until substantially free of residual sulfuricacid. About 10 parts by weight of calcium carbonate and 75 parts byWeight of water were then added to the precipitate and the mixture wasstirred until neutralization of the sulfonic acid contained in theoriginal brownish precipitate was complete. The precipitate of thecalcium salt of the sulfonic acid was then filtered off and extractedwith a 2:1 mixture by volume of ethyl acetate and water to removeextraneous .matter. The yield of calcium salt remaining was 78.6 partsby weight. From the solvent extract, 48 parts by weight of a neutralresin material were obtained by evaporation of the solvent. The purifiedcalcium salt was then acidified with dilute'sulfuric acid. A solution of10 parts by weight ofsodium carbonate in 600 parts by weight of waterwas then added to the sulfonic acid mixture and the solution filtered toremove calcium sulfate. By acidification of the filtrate with dilutesulfuric acid, the pseudopimaric acid sulfonate precipitated and wasremoved by filtration. The yield of dried and purified sulfonic acid ofpseudopimaric acid was 48 parts by weight. The sulfonic acid had a M. P.of 223-224 C. (with decomposition) It will be appreciated that thedetails and proportions set forth in the above are illustrative only,and that the invention as broadly described and claimed is in no waylimited thereby.

The sulfonic acid product will be found variously adapted to uses as animproved detergent and wetting out agent, e. g.,- in the scouring oftextiles, as a soap assistant, etc.

What I claimand desire to protect by Letters Patent is:

1. The method of preparation of a purified sulfonic acid which comprisestreating pseudopimaric acid with a sulfonating agent under sulfonatingconditions, treating the resulting sulfonated pseudopimaric acidreaction mixture with water'at a temperature below about 100 C. toprecipitate pseudopimaric sulfonic acid in crude form, washing outexcess sulfonating agent from the precipitate, treating the crudepseudopimaric sulfonic acid with a calcium salt reactive therewith toforma calcium salt of the pseudo pimaric sulfonic acid as a precipitatephase, extracting essentially neutral resin material from the calciumsalt maintained in the insoluble state with an organic solvent for theneutral resin material,

azsaeoa adding acid to the purified pseudopimaric sulfonic acid calciumsalt to form free pseudopimaric sulfonic acid and a water-insolublcalcium salt, and separating the calcium salt from the pseudopimaricacid sulfonate by dissolving the latter in aqueous alkali.

2. The method of preparation of a purified sulfonic acid which comprisestreating pseudo-- pimaric acid with concentrated sulfuric acid undersulfonating conditions, treating the resulting sulfonated pseudopimaricacid reaction mixture with water at a temperature below about 100 C. toprecipitate pseudopimaric sulfonic acid in crude form, washing outexcess sulfuric acid from the precipitate, treating the crudepseudopimaric sulfonic acid with a calcium salt reactive therewith toform a calcium salt of the pseudopimaric sulfonic acid as a precipitatephase, extracting essentially neutral resin material from the calciumsalt maintained in the insoluble state with an organic solvent for theneutral resin material, adding acid to the purified pseudopimaricsulfonic acid calcium salt to form the free pseudopimaric sulfonic acidand a waterinsoluble'" calcium salt, and separating the calcium saltfrom the pseudopimaric acid sulfonate by dissolving the latter inaqueous alkali.

TORSTEN HASSELSTROM.

